Effects of nomegestrol acetate on spontaneous and sulprostone-induced uterine contractions in pregnant cynomolgus monkeys monitored by telemetry.
OBJECTIVE
Our purpose was to study the effects of the progestomimetic compound nomegestrol acetate on spontaneous and sulprostone-induced uterine contractility in pregnant cynomolgus monkeys.


METHODS
Intrauterine pressure was continuously monitored with use of an implanted intraamniotic catheter and a telemetric pressure transmitter from day 115 to 135 of gestation (term = 165 days). After surgery the animals received either nomegestrol acetate (5 mg per day orally, n = 3) or vehicle only (controls, n = 3). The intramuscular prostaglandin E2 analog sulprostone (25 micrograms) was administered as a single injection 10 days after amniotic catheter implantation. Spontaneous and sulprostone-induced uterine contractions were compared between nomegestrol acetate- and vehicle-treated animals.


RESULTS
The frequency of spontaneous uterine contractions in control animals demonstrated a 24-hour pattern with a minimum at 12 hours and a maximum at 0 hours. The frequency of spontaneous contractions did not differ between nomegestrol acetate- and vehicle-treated animals. Sulprostone induced an increase in both the frequency and amplitude of contractions, reaching a maximum 12 hours after injection and fading out after 24 hours in vehicle-treated animals. In animals receiving nomegestrol acetate, the frequency of contractions increased moderately and transiently for a total duration of 6 hours only and returned to control levels thereafter.


CONCLUSIONS
Nomegestrol acetate significantly decreases the contractile response of the pregnant uterus induced by the prostaglandin E2 analog sulprostone.
Carbonne
B
B
Department of Obstetrics and Gynecology, Hôpital Saint-Antoine, Université Pierre et Marie Curie-Paris VI, France.
Cabrol
D
D
Clerget
M S
MS
Germain
G
G
D000020:Abortifacient Agents, Nonsteroidal / Q000494:pharmacology*; D000818:Animals; D002940:Circadian Rhythm; D015232:Dinoprostone / Q000031:analogs & derivatives* / Q000494:pharmacology; D005260:Female; D008252:Macaca fascicularis; D008535:Megestrol; D009649:Norpregnadienes / Q000494:pharmacology*; D011247:Pregnancy; D011270:Pregnancy, Animal / Q000502:physiology*; D045167:Progesterone Congeners / Q000494:pharmacology*; D013686:Telemetry; D013997:Time Factors; D014590:Uterine Contraction / Q000187:drug effects* / Q000502:physiology
D000020:Abortifacient Agents, Nonsteroidal; D009649:Norpregnadienes; D045167:Progesterone Congeners; C016767:sulprostone; C038501:nomegestrol acetate; D008535:Megestrol; D015232:Dinoprostone